The steering of snowmobiles is conventionally accomplished by a pair of ground engageable skis which are mounted on the front of the snowmobile and are turned in the direction in which the snowmobile is to be propelled. The turning radius of a snowmobile which is equipped with conventional skis, traversing very hard snow or ice is very large because the conventional ski runners merely slide along the surface without "digging in". To overcome this, snowmobile skis are provided with skags or keels on the underside thereof, having sharpened carbide wear rails which cut or bite into the hardened surface to positively control the turning of the snowmobile. The ability to positively control the path of movement of the snowmobile becomes particularly important in racing at high speeds.
When a carbide wear rail becomes worn, it is important that the skag assembly be so constructed that only the worn wear rail need be discarded and a substitute wear rail installed in its place. Accordingly, it is an object of the present invention to provide a snowmobile ski having a hardened wear rail removably clamped to the underside thereof to permit the hardened wear rail to be replaced by a substitute rail.
The wear rail, which is conventionally formed of carbide and is generally much harder and more brittle than the mounting member for the carbide rail, will crack or break upon sharp impacts. It has been found that if the upper leading edge of the hardened wear bar is protected, the incidence of breakage is reduced. Accordingly, it is an object of the present invention to provide a snowmobile ski runner having a hardened wear rail on the underside thereof and a guard which will protect the leading edge of the wear rail. Although it is important that the hardened wear rail be releasably clamped to the underside of the ski runner to permit its quick removal, it is imperative that the wear rail cannot be inadvertently dislodged from a ski runner mounted on a racing-type snowmobile. If the wear rail on a racing snowmobile is dislodged, the delay in halting the snowmobile and installing new wear rails can cause a snowmobile racer the loss of the race.
The skis on racing snowmobiles are subjected to particularly large stresses and repeated jarring which tends to dislodge the wear rail. The inadvertent loss of a wear rail when traveling at high speeds represents a safety hazard. If a racer attempts a sharp turn at high speeds without a wear rail, he will lose his steering capability which could cause him to leave the track and possibly hit other racers. Accordingly, it is another object of the present invention to removably couple a hardened rail to the underside of a snowmobile ski and positively preclude the wear rail from being jarred loose from the underside of a snowmobile ski.
It is yet another object of the present invention to provide a snowmobile ski rail having a hardened wear rail positively coupled thereto by elongate key members.
It has been found that the handling characteristics of some snowmobiles improve as the wear rails are moved to different locations along the underside of the ski. On some occasions, the machine will handle better if the wear rail comprises longitudinally spaced sections separated by a gap underlying the king pin. Accordingly, it is still a further object of the present invention to provide a keel for a snowmobile ski runner having interchangeable parts which permits a hardened wear rail mounted thereon to be positioned substantially anywhere along the underside of the ski runner.
Yet another object of the present invention is to provide a keel for a snowmobile ski having a pair of clamp members removably coupled to a hardened wear rail and adapted to be removably coupled to the underside of the ski runner.
Other objects and advantages of the present invention will become apparent as the description thereof proceeds.